Research on the Characteristics and Evolution of the Integration of Urban Agglomerations of Anhui and Yangtze River Delta Region

Qiaowei Yang Fei Shi

Abstract: Since the early 1980s when Yangtze River Delta Region embarked on the construction of urban agglomeration, its area has been enlarging continuously, and the spatial structure has been experiencing gradual evolution as well. At the same time, the urban agglomeration in Anhui Province is becoming more and more mature after experiencing a series of concepts of spatial planning. The existing literature stresses that economic factors will lead the spatial evolution of the YRDR, result in the breakthrough in the restriction of administrative divisions, and admit some area of Anhui with high carrying capacity and excellent resource to new members of the spatial network of YRDR. In light of this, the central government officially identified Anhui as a new member of the YRDR. This study builds on related data, conducting qualitative and quantitative analysis, to try to address two research questions: first, which areas of Anhui are expected to have bigger advantage during their integration into YRDR? Second, how will spatial structure of Anhui Urban Agglomeration evolve in the process?The results show that Chuzhou, Ma'anshan and Wuhu have bigger advantage during their integration into the YRDR, and three changes in Anhui Urban Agglomeration are expected to happen, which includes an urban belt including Chuzhou, Ma'anshan and Wuhu, a new Suzhou（Anhui）-centred economic circle, and a large central city might rise in the south of Anhui.

Key Words: Anhui; Yangtze River Delta Region; urban agglomeration;integration

Introduction

Against the background of“One Belt One Road”initiative, the Yangtze River Delta Region（hereinafter called the“YRDR”）is expected to play a leading role in promoting this great national strategy（Chen, 2015）. Scholars argue that members of the YRDR such as Shanghai（Wang, 2015）, Ningbo（Dai, 2014）and cities of Jiangsu Province（Yang, 2015）are expected to take advantage of the opportunity to seek boost in future development.

The YRDR is in coastal area in east China which consists of Shanghai City, Jiangsu Province, Zhejiang Province and part of Anhui Province, covering about more than 210740 square kilometres' area and a total population of 154 million excluding the part of Anhui Province.

As early as 1970s, Jean Gottmann（1976）in his paper Megalopolitan Systems around the World identified the potential sixth Megalopolitan area in the world centered on Shanghai, although few people realized that at that time. To date, the YRDR has became the most developed area of China, playing an important role in the development of Chinese cities and economy in littoral areas of China, and even in the development of Asia-Pacific Region（Gu et al. , 2007）. In 2010 scholars contend that the Yangtze River Delta has become the sixth largest urban agglomeration in the world（Fang et al. , 2011）.

For a long time, the area of Yangtze River Delta as well as the scope of related research or statistical data had been concentrated on the old or traditional region which only encompasses Shanghai, Jiangsu and Zhejiang. However, in September 2014, the State Council released a document officially placing Anhui Province as a member of the Yangtze River Delta Urban Agglomeration（State Council of China, 2014）. In June 2016, the central government issued the planning for the development of the YRDR Urban Agglomeration, further identifying the participation and position of Anhui in the YRDR（National Development and Reform Commission, 2016）.

Anhui Province borders Jiangsu Province to the east, and Zhejiang Province to the southeast. At the end of 2015 the population of Anhui was about 61436000, and the urbanization rate was 50.5%. Anhui's GDP per capita in 2015 was 35997 RMB yuan, which equals 5779 US dollars（APBS, 2016）.

Apparently, it can be identified from the figures showed above that Anhui's economic development is far behind its neighbours in terms of either the total GDP or GDP per capita. What's more, Anhui's proportion of the first, second and third industry was 11.2∶51.5∶37.3（APBS, 2016）, which indicated that the province was still in the early or middle stage of the process of industrialization compared with other parts of China（Yi, 2010）. As a matter of fact, Anhui has been positive to join YRDR since early 1980s. But the significant economic gap between Anhui and the YRDR might be the biggest obstacle in blocking Anhui's participating.

On the other hand, however, Anhui has its advantages of location and resource（Jiang, 2010）; science and education foundation, associated industries（Qin, 2015）. Some scholars also contend Anhui shares the same regional culture and common values with the YRDR, which is also an positive factor in helping Anhui's participation（Guo and Zhu, 2012）. Thus, Anhui's integration into the Yangtze River Delta Urban Agglomeration can not only promotes the faster and better economic development of Anhui Province, but also promotes the integration and development of the YRDR（Zhao, 2015）.

Nevertheless, due to regional disparity, even though the policies have identified Anhui as a member of the“club”, the argument about the role and position of it in the YRDR still exist. For instance, Yao, who is the founder of the concept of“urban agglomeration”of China, contends that only some more relatively developed parts of Anhui could be absorbed into the Yangtze River Delta Urban Agglomeration, but not the entire Anhui Province, because the urban agglomeration is a developed region with sound transportation network（Yao et al. , 2015）.

Therefore, based on the argument of Yaoet al.（2015）, this study focuses on addressing two research questions: first, which areas of Anhui are expected to have bigger advantage during their integration into the YRDR? Second, how will spatial structure of Anhui Urban Agglomeration evolve in the process？

Literature Review

1．Outline of the spatial evolution of the YRDR

The construction of the YRDR Urban Agglomeration started in early 1980s when the reform and opening-up policy was implemented. Since then, the construction land increased rapidly with the attainment of economic goals and growth of comprehensive strength（Wang et al. , 2015）. In the meantime, the region's spatial structure was evolving continuously（Li, 2010）. Taking the perspective of the whole developmental course, it can be identified that the urban growth and evolution model in different temporal-spatial dimensions reflect interactions of various factors, which includes adjustment of policy（Tian et al. , 2011）, for example, the reform of economic policy（Wang et al. , 2016）;economic growth（Tian et al. , 2011）, for instance, the market forces（Wang et al. , 2016）; and city's administrative status（Wang et al. , 2015; Wang et al. , 2016）.

More specifically, at the policy level, the State Council established the Shanghai Economic Zone Planning Office in 1982, local governments established organizations, such as the Yangtze River Delta Economic Open Zone and the Economic Coordination Committee for Central Yangtze River Coastal Cities in 1985. All these governmental actions were aimed to enhance the regional cooperation. However, as Zhu（2015）points out that, the Shanghai Economic Zone Planning Office had limited impact, and the Economic Coordination Committee paid more attention to its own local interests, lacking legislative status and efficiency of implementing policy, thus, at the beginning, the optimisation of spatial structure of YRDR agglomeration was short of governance at the regional level. In spite of this, the implication of policy for the spatial evolvment of the YRDR is remarkable. Zhang et al.（2011）find that although since 1990 the YRDR experienced rapid increases in urbanization and Land Use Change（LUC）, a slowdown in LUC during the period of 1995-2000 may presumably be due to the adjustment of national policy, for example, the enactment of the law on Farmland Protection Regulation in 1994.

Compared with policy, the influence of economic factors is more prominent, and the continuous evolution of the regional spatial structure is closely related to its economic layout（Li, 2010）. The coalescence process that is characteristed with infilling and edge expansion is the major growth type for the YRDR cities（Tianet al. , 2011）. In terms of the edge expansion, Zhang et al.（2009）argue that this growth model is realised by low-end industries' seeking increase in low cost construction land at city edge.

The administrative level is another factor that can not be ignored. Zhou and Zhang（2003）argue that the YRDR has a single-center spatial structure, and the central city Shanghai expands continuously and influence nearby cities. Drawing on the GIS remote sensing data of 1991, 2001 and 2008, Wang et al.（2015）also find that areas where governmental departments are located tend to be the growth center of construction land, hence, Shanghai takes the greatest percentage, and prefecture-level cities were the fastest growth region.

Under the combined action of these factors stated above, the YRDR's spatial structure is always in a dynamic developmental condition. Looking back on the developmental course of the region, its evolution of spatial structure can be divided into the four stages that are presented as follows：

The first stage was in 1980s. The YRDR's economic activities were centralized on Shanghai, Nanjing and Hangzhou, thus, the spatial structure showed a punctiform layout of“V”, in which Shanghai was the core, and Nanjing and Hangzhou were the sub cores（Li, 2010）. Up till now, Shanghai's vital function in the YRDR's development is still widely recognised in literature, indicating that its leading position can not be challenged（Cao, 2010; Zhang and Ning, 2011）. In addition, Jing（2007）contends that future spatial structure will be in the shape of“finger”, in which Shanghai still play the role of the“core”, and four high speed traffic lines will be the ties.

The second stage started with the rise of Pudong, Shanghai. Since the implementation of development and opening policy in 1992, Pudong New District has become a new economic growth point in the YRDR, promoting neighbouring area's development as well. During this period, the regional spatial structure formed“Z”axis model that spread along Hu-Ning（Shanghai-Nanjing）, Hu-Hang（Shanghai-Hangzhou）and Hang-Yong（Hangzhou-Ningbo）traffic lines（He, 2007）. After Pudong became the central area of the new national strategy of a new wave of reform, the economic growth of Shanghai and the entire YRDR was fast tracked with different development models（Wanget al. , 2016）. In other words, the rise of Pudong should be attributed to the reform of policy as well as the enlargement of local governments' power（Zhang et al. , 2009）.

The third stage saw the rise of Suzhou, Wuxi and Ningbo, which made the YRDR began to form multi-center, network layout. The construction of traffic infrastructure played an critical role in the process. He（2007）argues that the development of motorway and high speed train will bring further major change for the spatial structure of the YRDR. What is more, as a result of the construction of waterway infrastructure, the YRDR Urban Agglomeration evolved from“Z”axis model to reverse“K”model（Li, 2010）. In summary, the spatial structure of the YRDR Urban Agglomeration is a layout that expands along main water body, such as the Yangtze River and Taihu Lake as well as main traffic lines, such as Hu-Ning（Shanghai-Nanjing）Railway and Hu-Hang（Shanghai-Hangzhou）Railway, merging to form“∑”spatial model（Jing, 2007）.

Based on the review on these three stages, exiting literature summarises the feature of developmental course of the spatial structure. Li（2010）argues that the YRDR Urban Agglomeration's spatial structure evolves from a layout of single-center, one-way connection towards a multi-center, networking, flat one. Similarly, Shi（2010）and Jing（2007）contend that the spatial structure evolves from pole-axis model to networking model. Wanget al.（2016）point out that the level of the YRDR Urban Agglomeration's spatial heterogeneity keeps declining, reflecting a relatively dispersed and intensified urban network with new urban nodes emerging in the regional spatial structure. Zhu and Zheng（2012）also argue that a spatial structure model of single-core and multi-centre should be the ideal condition for the YRDR Urban Agglomeration's spatial evolution. Likewise, Zhang and Xu（2007）identify that according to the developmental experience of mature urban agglomerations oversea, spatial structure's flatting will be more beneficial to joining global competition.

In the fourth stage economic factors will play a leading role in the spatial structure's evolution of the YRDR, breaking through the restrictions of administrative division, therefore, prosperous cities in Anhui are expected to be included the regional integration of the YRDR（Shi, 2010）. Furthermore, drawing on the previous three stages' development, it can be identified that the regional morphology will be developing towards a multi-centre, flating structure. Based on the research on the carrying capacity of the YRDR's cities, Liu（2012）concludes that the urban agglomeration should appropriately guide the population and industries to small and medium cities of higher carrying capacity.

Needless to say, cities of Anhui have better carrying capacity than the counterparts of the YRDR. Apart from that, Anhui's traffic infrastructure that keeps improving, in particular the construction of high speed railway along the Yangtze River provides material base for the spatial extension of the YRDR.

2．Outline of the spatial evolution of Anhui Urban Agglomeration

By viewing on existing literature, for example Guo（2010）, Yang et al.（2012）and Ni（2009）, it can be identified that during the process of development of Anhui urban agglomeration, a series of concepts such as economic zone, metropolitan circle, urban belt, economic circle, urban circle, urban agglomeration, appeared in sequence. The proposal of these concepts shows that Anhui urban agglomeration has been more and more mature. Through viewing on the developmental course of the region, the researchers identify that the evolution of its spatial structure can be divided into three stages that are showed as follows.

The first stage is the starting phrase. This phrase focused on the construction of“pole-axis”, developing the rudiments of the economic zoning to promote the regional economic development by the“pole”and“axis”. For instance, Anhui proposed the“Three Zones One Center”strategy, i. e. , Huainan-Huaibei Economic Zone, Economic Zone along the Yangtze River, South Anhui Tourism Zone, and Hefei Science Education Centre. In 2000, “One Pole Double Axis”was proposed, which encompassed the south-north axis that was based on Hefei Metropolitan Circle, high-tech industries of Hefei and tourism resources of Huangshan; and the east-west axis that used the traffic advantage of the Yangtze River. In 2002, the concept of“Urban Belt of Hefei, Wuhu and Anqing”, which was based on Hefei, Wuhu and Anqing as the centre, and north and south Anhui as the economic base in order to develop three-hour“He-Wu-An”economic circle.

The second stage is the forming development phrase. This phrase paid more attention to the characteristics of regional economy and using local advantages. For example, in 2003“Hefei Economic Circle”was proposed, which included Hefei（the central city）, Bengbu, Chuzhou, Chaohu and Wuhu. In 2004“9 plus1”Urban Circle took Hefei as the central city, covering other nine cities including Wuhu, Ma'anshang, Tongling, Anqing, Huainan, Luan, Chaohu, Chuzhou and Chizhou. In 2006, Anhui Urban Agglomeration was divided into three major regions according to the characteristics of local economy, which comprised the Huaihe River Urban Agglomeration, the Yangtze River Urban Agglomeration and the Provincial Capital Economic Circle.

The third stage is the expanding development phrase. In this phrase, the three major urban agglomerations that were proposed in 2006 continued to seek expansion and connection with other regions. For instance, in 2008 the“Huai-Yangtze River Urban Agglomeration”was proposed, which consisted of Hefei and other eleven prefecture-level cities. Based on the Provincial Capital Economic Circle in 2009 the Hefei Economic Circle was proposed, which covered Hefei, Huainan, Luan, Chaohu and Tongcheng. In 2010 the Yangtze River Urban Agglomeration further developed into Wan Jiang Urban Agglomeration including Hefei, Wuhu, Ma'anshan, Tongling, Anqing, Chizhou, Chaohu, Chuzhou, Xuancheng and parts of Luan.

The fourth stage is the integrating development phrase. In other words, being different from the previous three counterparts, the fourth phrase concentrated on the construction of one core area and the integration into the YRDR. In 2010, the State Council approved the implementation of the Plan of Industry Transfer Demonstration Zone of Wan Jiang Urban-City Region, aiming to build a closer tie between Anhui and the YRDR. In July 2011, Chaohu was put under the administration of Hefei, Wuhu and Ma'anshan, building a tighter economic tie between Hefei and Wuhu, which was helpful to the construction of the“Greater Hefei”as well as the cooperation between Hefei Economic Circle and Wan Jiang Urban Belt.

Methods

The developmental courses of both Anhui and the YRDR indicate that in most cases policy goes before the evolution of spatial structure of the urban agglomeration. In other words, the stimulating function of policy clears many obstacles for the regional development. Fortunately, Anhui has got enough political supports from the central government in the process of its integration into the YRDR.

But, nonetheless, rather than the policy, the experience of the YRDR as well as other mature, developed urban agglomerations shows economic factor is the most important driver of development. Therefore, in other words, Anhui would not integrate soundly only by using political resource, unless this province could build tight economic ties with the YRDR.

Hence, the researchers use the economic ties strength model as well as the economic hierarchy index model to calculate the cities'economic ties and the city's economic hierarchy（Shiet al. , 2014）. These models are presented as follows：

（1）The economic ties strength model

Where Tij is is the economic tie of city i to city j; P i and P j are the populations of city i and city j; G i and G j are the GDP values of city i and city j;and D ij is the operating distance of the high speed railway between two cities. For cities that have no high speed railway, the distance of them from the others, which is for ordinary railway, will be multiplied by coefficient（value=2）.

（2）The economic hierarchy index model

Where Hiis the economic hierarchy of city i, and Tijis the economic tie of city i to city j.

The economic ties strength indicates economic links and direction of economic linkages among cities. By analysing the economic ties between Anhui Urban Agglomeration and the YRDR Urban Agglomeration, the researchers will further explore cities of Anhui Urban Agglomeration thatare expected to have bigger advantage during their integration into the YRDR. Furthermore, the economic hierarchy index can reflect the centrality of city, which can be used to reveal that promoting economic ties between cities that have stronger centrality will be helpful to the integration of urban agglomeration as well as the integration of nearby cities.

The research took prefectural city as a study unit, and all data was from local governments'“Statistic Communique on National Economic and Social Development”as well as other official statistic sources. In terms of the selection of study cities, the researchers selected all Anhui cities and 10 counterparts of the YRDR for further investigation. With regard to the selection of study cities of the YRDR, the researchers took into consideration the distance of them from their counterparts in Anhui, and their economic status in the region.

Results and Discussion

The values of the economic ties strength and centrality are showed in the Table 1. By using the Formula（1）, the researchers got the result showing that Hefei, Chuzhou, Ma'anshan, Suzhou（Anhui）and Wuhu in Anhui had stronger economic ties with their counterparts in the YRDR, and their values were 623.57, 776.35, 1005.89, 500.69, 521.73 respectively, which were far larger than that of the other cities in Anhui. Among these five Anhui cities, Ma'anshan had the best economic hierarchy status（value=0.24）, Chuzhou is the second（value=0.18）and Hefei the third（value=0.15）. In the YRDR, Nanjing was found to have the strongest economic connection with cities in Anhui（value =2377.3）, and the highest economic hierarchy index（value=0.56）, while Xuzhou was the second one（the values were 670.76 and 0.16 respectively）.

Therefore, based on the result of the economic ties strength, the researchers draw the diagram of economic ties between Anhui and the YRDR（see Fig 1）. From the results and the figure, it can be identified that Nanjing would play a critical role or even a leading role in the Anhui Urban Agglomeration's integration into the YRDR. In other words, the development of Anhui Urban Agglomeration, especially cities such as Chuzhou, Ma'anshan and Wuhu are all strongly influenced by Nanjing. Based on this commonality of them, the researchers infer that Chuzhou, Ma'anshan and Wuhu might form a new north-south economic or urban belt in the east of Anhui Urban Agglomeration, and the three cities'economic ties would become stronger as long as they could develop in cooperation. In terms of this, however, there still exist a traffic obstacle that can be identified, because Chuzhou has no high speed railway connecting to Ma'anshan and Wuhu.

For the provincial capital Hefei, although its location in the province influences its connection with the YRDR, the city shows relatively strong economic ties with big cities in the YRDR such as Nanjing, Shanghai and Suzhou（Jiangsu）. This should be attributed to Hefei's relatively large GDP and population. Thus, for the sake of keeping this advantage, the researchers infer that Hefei should build stronger ties with Chuzhou, Ma'anshan and Wuhu, to enlarge the economic status of the“Greater Hefei”. And by promoting the development of the core area in Anhui, this area will be able to build stronger ties with cities like Nanjing, which is helpful to the integration of the Anhui Urban Agglomeration.

In the north Anhui, Suzhou（Anhui）is the only city that has strong ties with the YRDR, especially Xuzhou. Therefore, for the other cities in North Anhui, the researchers argue that a new Suzhou（Anhui）-centred economic circle might be a reasonable spatial structure in the future. Unfortunately, the current traffic condition of some of them might be a big obstacle, for instance, cities such as Bozhou and Huaibei are still unable to get access to high speed railway.

The inference stated above supports the previous developmental strategy and course of the Anhui Urban Agglomeration, which is presented in the section of literature review. And it also verifies that Anhui Urban Agglomeration is becoming more and more mature. What is more, with the continuous improvement in traffic condition, more and more cities in Anhui would build stronger ties with the YRDR. Therefore, it can be expected the whole Anhui Province would integrate into the YRDR completely.

Furthemore, in the YRDR central cities like Shanghai and Hangzhou, do not have strong economic ties with Anhui cities necessarily, mainly due to the factor of distance. But for the cities in south Anhui, the researchers contend that another important reason why they do not have strong ties with the YRDR is their own strength instead of the distance, for example, cities like Xuancheng and Huangshan have relatively small population and GDP. But, nonetheless, compared with the counterparts in the north Anhui, they have better traffic condition and economic base, thus, the construction of one regional central city might be the first step to break through the current developmental bottleneck. In light of this, in the future, the south Anhui need to form a central city to build stronger ties with the YRDR, especially Hangzhou.

Conclusion

It is clear from the analysis on the result that cities in Anhui including Chuzhou, Ma'anshan and Wuhu have bigger advantage during their integration into the YRDR, what is more, Hefei and Suzhou（Anhui）also have relatively strong economic ties with the YRDR. During the process of Anhui's integration, Nanjing is the most important city in the YRDR that could have significant implication.

Based on the economic ties, with continuous improvement in traffic condition and economic base, some changes in Anhui Urban Agglomeration can be inferred. First, a new south-north economic or urban belt including Chuzhou, Ma'anshan and Wuhu is expected to appear in east Anhui. Second, in the north part of the province, a new Suzhou（Anhui）-centred economic circle could form. Third, for the south Anhui, a large central city might rise in the future in order to build strong economic ties with Hangzhou.

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（PhD candidate, School of Architecture, Planning and Landscape, Newcastle University, Newcastle upon Tyne, UK.

Associate professor, School of Civil Engineering and Architecture, Suqian College, Suqian, Jiangsu, China）